Effect of cardiac rehabilitation on endothelial function in smoker patients with ischemic heart disease

Background: smoking enhances the risk of cardiac events in patients with coronary artery disease. So, it is necessary to evaluate the effects of exercise-based cardiac rehabilitation on endothelial function and functional capacity among smoker patients. Methods: This randomized clinical trial study was conducted on 56 non-diabetic smokers with a history of percutaneous coronary intervention or coronary artery bypass graft surgery in Imam Khomeini Hospital from May to August 2015. Based on cardiac rehabilitation, patients were divided into intervention and control groups. Before rehabilitation, fasting blood sugar (FBS), lipid profile (LDL, HDL, triglyceride, and total cholesterol), and Ankle-Brachial Index (ABI) were measured for endothelial function. Besides, METs were measured based on the Duke activity status index. After 24 rehabilitation sessions (3 sessions of 1 hour each week for 2 months), all values were checked again and compared with the initial values. Results: The mean age of the subjects in the cardiac rehabilitation and control groups were 61.18 and 52.32, respectively. Before the intervention, there were no significant differences between the two groups in terms of the ABI variables, BMI, systolic and diastolic blood pressure, LDL, triglyceride, total cholesterol and FBS; only HDL and METs showed significant differences. After exercise-based cardiac rehabilitation, the mean rate of ABI changes was +0.078 on the right side of the body and +0.084 on the left side of the body. In the control group, these values were 0.002 and 0.003, respectively (P=0.001). The amount of changes in increasing METs as well as decreasing body mass index (BMI), and systolic and diastolic blood pressure in the rehabilitation group were statistically significant compared to the control group. In addition, there were no significant differences in terms of FBS and lipid profiles either (P>0.05). Conclusion: Two months of cardiac rehabilitation with regular exercise was associated with improved ABI as an indicator of endothelial function and prognosis of cardiovascular disease, as well as improved cardiac functional capacity among smoker patients.